1. Field of the Invention
The present general inventive concept relates to an image forming apparatus, and more particularly to an image forming apparatus that is equipped with a waste toner storage device to collect residual waste toner on an image carrying body after printing an image.
2. Description of the Related Art
A conventional image forming apparatus is an apparatus that prints an image on a printing medium, e.g., paper, according to an input image signal. One type of the image forming apparatus, an electrophotographic image forming apparatus, is configured such that a light beam is scanned to a photosensitive member charged with an electric potential to form an electrostatic latent image thereon. Subsequently, the electrostatic latent image is developed into a toner image by supplying a developer (toner, or toner and carrier) to the electrostatic latent image, and the toner image is transferred and fixed to paper.
The conventional image forming apparatus includes a main body which forms an exterior appearance, a print unit which is mounted inside the main body, a paper supply unit which supplies paper to the print unit, and a paper discharge unit which discharges the printed paper outside of the main body. Referring to a conventional color image forming apparatus, the print unit includes a developing unit which forms yellow, magenta, cyan and black toner images on the respective photosensitive members, a transfer unit which transfers the toner images formed on the photosensitive members onto the paper, and a fixing unit which applies heat and pressure to the paper to fix the toner images to the paper.
The conventional image forming apparatus further includes a cleaning unit which removes waste toner generated by the photosensitive members of the developing unit and the transfer belt of the transfer unit during the repeated printing process, and a waste toner storage device which stores the waste toner collected by the cleaning unit.
Japanese Patent Laid-open Publication No. 2002-229402 discloses a waste toner collecting device of an image forming apparatus. The disclosed conventional waste toner collecting device includes a waste toner container and a vibration device for vibrating the waste toner container. By vibrating the waste toner container using the vibration device, the waste toner accumulates evenly (not in a mountain-shape) in the container. The reason for necessitating the vibration device is that the waste toner contains impurities like fibrous components of paper from the printing process and has low fluidity and high cohesiveness when compared to a new toner. However, the conventional waste toner collecting device has the problem that the size of the device becomes large due to the installation of the vibration device around the waste toner container.
Another exemplary conventional waste toner storage device includes a screw by which the waste toner accumulates evenly in the container. However, if the waste toner accumulates to a certain extent, a borehole is formed around the rotating screw, and the waster toner accumulates in a mountain-shape thereon. Also, the overall capacity of the waste toner storage device decreases from inclusion of the screw.